The invention relates to a method for monitoring a measurement device, in particular a flow measurement device, and to a measurement device itself.
Measurement device monitoring systems are widely known. This applies in particular to test equipment which is connected to a bus system via which measurement data is transported in one direction and control data is transported in another direction.
The invention relates in particular to flow measurement devices, in which case a control procedure such as this can also be applied to other measurement devices, provided that these measurement devices determine measurement data from analysis or from a process.
In the case of flow measurement devices, a distinction is drawn between different measurement effects or principles. For example, some measurement devices determine the flow of a fluid capacitively, magnetically or by vortex formation on a flow body. Devices which use the last-mentioned measurement method are referred to as vortex flow measurement devices.
Test equipment such as this determines the flow velocity in a pipeline in a know manner on the basis of the Karman vortex street: a flow obstruction in the pipeline segment of the test equipment produces periodic vortices downstream, whose frequency is a measure of the flow velocity. The vortex signal is converted by suitably tapping off the periodic vortices (for example by means of a paddle or an ultrasound sensor) to an electrical signal whose frequency is a measure of the flow velocity.
Owing to their method of operation, the reliability of such vortex flow measurement devices is highly dependent on the physical state of the fluid. For example:                a tilted installation of the test equipment,        curves in the pipeline,        a pulsating fluid flow,        vibration of the pipelines and        turbulence upstream of the flow obstructioninfluence the measurement accuracy and the reliability of this test equipment. Installation instructions which are intended to ensure correct use of the vortex flow measurement devices have admittedly been written. However, even when the installation instructions are complied with, there is no guarantee of the reliability not being influenced by effects such as these. Furthermore, even for experienced specialists, it is sometimes difficult to identify the presence of disturbing effects. For example, even relatively minor tilt angles in the installation lead to addition vortex formation in the fluid, with these vortices being superimposed on the actual, desired measurement signal, and influencing the measurement accuracy.        
The invention is thus based on the object of specifying a method as well as a measurement device itself by means of which measurement errors such as these resulting from incorrect installation are reliably avoided.